A multilayer ceramic capacitor, a multilayer chip electronic component, is a chip-type condenser installed on the printed circuit boards (PCBs) of various electronic products such as image display devices (or video display apparatuses) including liquid crystal displays (LCDs), plasma display panels (PDPs), and the like, as well as computers, personal digital assistants (PDAs), cellular phones, and the like, to charge or discharge electricity.
A multilayer ceramic capacitor (MLCC), having advantages such as compactness, guaranteed high capacitance, and ease in the mounting thereof, may be used as a component of various electronic devices.
Such an MLCC may include a plurality of dielectric layers and internal electrodes and may have a structure in which the internal electrodes having opposing polarities are alternately disposed between the dielectric layers.
The dielectric layers may have piezoelectric and electrostrictive properties. Thus, when a direct current (DC) or alternating current (AC) voltage is applied to an MLCC, a piezoelectric phenomenon may occur between internal electrodes, thereby generating vibrations.
Vibrations may be transferred to a PCB on which the MLCC is mounted, through solders of the MLCC, leading to the entirety of the PCB acting as an acoustically radiating surface to generate vibratory sound as noise.
Vibratory sound may correspond to audio frequencies ranging from 20 Hz to 20,000 Hz, causing listener discomfort, and such a vibratory sound, which may cause listener discomfort, is commonly known as acoustic noise.
In order to reduce acoustic noise, a product in which a thickness of a lower cover layer of an MLCC is increased has been studied.
However, further research into a product having improved acoustic noise reduction effects is required.